Burglar-alarm.



No. 700,652. Patented May 20, I902.

G. JANKE.

BUBGLAR ALARM.

(Application filed Dec. 31, 1801.)

(No Model.)

M a QLOMMM UNITED STATES PATENT OFFICE.

GUSTAV JANKE, OF ALGOMA, WISCONSIN.

BURGLAR ALARM.

SPECIFICATION forming part of Letters Patent No. 700,652, dated May 20,1902. Application filed December 81, 1901. Serial No. 87,934. (Nomodel.)

To all whom it may concern:

Be it known that I, GUSTAV J ANKE, a citizen of the United States,residing at Algoma, in the county of Kewaunee, State of Wisconsin, haveinvented certain new and useful Improvements in Burglar-Alarms; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

This invention relates to burglar-alarms; and it has for its object toprovide a device of this nature which may be attached to the jamb of adoor in such position that when the door is closed the electricalcontacts will be held out of engagement and when the door is opened themovable contact will be permitted to engage the opposing contact underthe influence of its actuating-spring to close an electric circuitincluding a hell or other form of alarm.

Other objects and advantages of the invention will be understood fromthe following description.

In the drawings forming a portion of this specification, and in whichlike numerals of reference indicate similar parts in the several views,Figure 1 is a perspective View showing the device applied to adoor-frame, the door being closed to hold the contacts out ofengagement. Fig. 2 is an elevation showing the parts in their positionswhen the contacts are in engagement.

Referring now to the drawings, the present invention includes abase-plate 5, upon which is disposed a'fixed contact 6 in the path ofmovement of a second contact in the form of an arm '7, which is pivotedupon the baseplate, the contacts having the circuit-wires 8 and 9attached thereto and to a bell l0 and battery 11 in the usual manner,the bell and battery being also connected, so that when the contacts arein engagement the circuit of the battery will be closed through the belland the latter will be operated.

Upon the base 5 is the post 12, through the lower end of which is theguideway 13, in which is disposed the slide-bar 14:, having a reducedend portion 15, which engages slidably the guiding-eye 16 upon the base,while at the opposite end of the slide-bar is pivoted a link 1.7,pivoted at its outer end to the outer end of the post, as shown. In theslide-bar is an opening 18, and in this opening is engaged the reducedouter end of the movable contactarm, so that when the slide-bar is movedin one direction the arm will be moved from engagement with the fixedcontact and when the slide-bar is moved in an opposite direction themovable arm will be engaged With the fixed contact. To move and holdthecontactarm in yieldable engagement with the fixed contact, a leaf-spring20 is provided, one end thereof being engaged with a stud 21 upon thebase, while the opposite end bears against the shoulder 22, adjacent tothe reduced portion of the bar. The spring holds the slide-bar normallywith the link at an acute angle to the base-plate and projecting withits inner end therebeyond, the plate in practice being mounted, asshown, in the door-casing, so that the link lies in the path of movementof the door when the latter is closed, the door striking the link andsliding along it and forcing it rearwardly against the action of theleafspring until the door has passed beyond the end of the link and theblock 23 on the door moves into position against the end of the link,the block then holding the link with the contacts out of engagement.When the door is opened, it passes from engagement with the link, sothat the slide-bar is released and the contact-arm moves into engagementwith the fixed contact under the influence of the leafspring to closethe circuit of the battery through the bell to sound the latter. Thus itwill be seen that with this construction when the door is open thecircuit is closed and when the door is closed the circuit is open. Aswitch 25 is disposed in the circuit, so that the mechanism describedmay be rendered inoperative to close the circuit when desired.

In practice modifications of the specific con struction shown may bemade and any suitable materials and proportions may be used for thevarious parts without departing from the spirit of the invention.

/Vhat is claimed is 1. A device of the class described comprisingrelatively fixed and movable contacts having means for holding them innormal and yieldable engagement, and a pivoted member connected with themovable contact for moving and releasing it when said mom ber is movedpivotally, said pivoted member projecting at an angle to the path ofmovement of the movable contact for engagement by a door to move andhold it with the contacts out of engagement.

2. A device of the class described comprising a base having a fixedcontact thereon, a pivoted contact-arm disposed for engagement with thefixed contact, a slide-bar with which the arm is connected, a springengaged with the slide-bar to hold it yieldably with the contacts inengagement, a post, and alink pivoted to the post and to the slide-barand arranged for engagement by a door to move and hold it against theaction of the spring.

8. Adevice of the class described compris-

